AP4E1 explained

AP-4 complex subunit epsilon-1 is a protein that in humans is encoded by the AP4E1 gene.^[1]

Function

The heterotetrameric adaptor protein (AP) complexes sort integral membrane proteins at various stages of the endocytic and secretory pathways. AP4 is composed of 2 large chains, beta-4 (AP4B1) and epsilon-4 (AP4E1; this gene), a medium chain, mu-4 (AP4M1), and a small chain, sigma-4 (AP4S1).^[1]

Clinical relevance

It is currently hypothesized that AP4-complex-mediated trafficking plays a crucial role in brain development and functioning.^[2]

Further reading

• Dell'Angelica EC, Mullins C, Bonifacino JS . AP-4, a novel protein complex related to clathrin adaptors. . J. Biol. Chem. . 274 . 11 . 7278–85 . 1999 . 10066790 . 10.1074/jbc.274.11.7278. free .
• Hirst J, Bright NA, Rous B, Robinson MS . Characterization of a fourth adaptor-related protein complex. . Mol. Biol. Cell . 10 . 8 . 2787–802 . 1999 . 10436028 . 10.1091/mbc.10.8.2787. 25515.
• Takatsu H, Futatsumori M, Yoshino K . Similar subunit interactions contribute to assembly of clathrin adaptor complexes and COPI complex: analysis using yeast three-hybrid system. . Biochem. Biophys. Res. Commun. . 284 . 4 . 1083–9 . 2001 . 11409905 . 10.1006/bbrc.2001.5081 . etal.
• Boehm M, Aguilar RC, Bonifacino JS . Functional and physical interactions of the adaptor protein complex AP-4 with ADP-ribosylation factors (ARFs). . EMBO J. . 20 . 22 . 6265–76 . 2001 . 11707398 . 10.1093/emboj/20.22.6265 . 125733.

Notes and References

1. Web site: Entrez Gene: adaptor-related protein complex 4.
2. Abou Jamra R, Philippe O, Raas-Rothschild A, Eck SH, Graf E, Buchert R, Borck G, Ekici A, Brockschmidt FF, Nöthen MM, Munnich A, Strom TM, Reis A, Colleaux L . Adaptor Protein Complex 4 Deficiency Causes Severe Autosomal-Recessive Intellectual Disability, Progressive Spastic Paraplegia, Shy Character, and Short Stature . Am J Hum Genet . 88. 6. 788–95. May 2011 . 21620353 . 10.1016/j.ajhg.2011.04.019 . 3113253.